On Thu, 28 Aug 2025 07:46:36 GMT, Stefan Karlsson <[email protected]> wrote:
> While investigating > [JDK-8260555](https://bugs.openjdk.org/browse/JDK-8260555), which lowers the > timeout factor from 4 to 1, we found that FDLeakTest sometimes times out on > Linux. > > The reason is that the test performs a `fcntl` call for each and every > potential file descriptor number. This can be a large number of calls and > sometimes results in minutes-long test executions. > > I propose that we fix this by limiting the max number of open file > descriptors. This lowers the test execution time to about 1 second. > > The test has two processes. One that executes the libFDLeaker.c code below as > an agent in the test JVM, then it forks into a exeFDLeakTester.c, which reads > the property `int max_fd = (int)sysconf(_SC_OPEN_MAX);`. The setting of > `RLIMIT_NOFILE` to `100` lowers `max_fd` to `100`. I've verified this on both > Linux and on macOS. > > I've run the test manually on Linux and macOS and verified that it runs > faster. I've also run this through tier1. This pull request has now been integrated. Changeset: 3abaa836 Author: Stefan Karlsson <[email protected]> URL: https://git.openjdk.org/jdk/commit/3abaa83610efb5c8e9b86c6f895d6b58d21e1fa2 Stats: 42 lines in 2 files changed: 39 ins; 0 del; 3 mod 8366298: FDLeakTest sometimes takes minutes to complete on Linux Reviewed-by: lkorinth, rriggs, stuefe ------------- PR: https://git.openjdk.org/jdk/pull/26979
